Seat cushion



Feb. 18, 1941. l R. M. s'll'oNE ETAI.A

SEAT CUSHION Filed July 22, '1938 f Patented Feb. 18, 1941 UNITED STATES PATENT OFFICEl snsjr cUsnroN Applicants .rally 22; 193s, serial No. 220,164

claims. mi. 155-119) 'I'his invention relates to seat cushions, more especially to seat cushions for use under varying atmospheric pressures, or load conditions.

Parachute seat cushions are a good example Al5 of cushions of the foregoing class and heretofore pneumatic parachute seat cushions have been provided so that the air pressure set up inside the seat cushion may be varied with changes in 'm the atmospheric pressure existing at the different altitudes at which the parachute seat cushion is used, However, these cushions would collapse, or bottom frequently as well as easily being distorted out of shape when under low pressure. Y

The object of this invention is to overcome'the foregoing and other objections to known -types of parachute seat cushions and to provide a seat cushion for use under varying atmospheric pressures which cushion is positively prevented from bottoming or being distorted from its' original shape while also being adapted for use under various atmospheric pressures.

Briefly stated, the invention comprises inserting a sponge rubber pad into a fabric cover that is rendered air-tight by spraying latex thereon. A valve is associated with the covering means so that the air pressure existing within the cushion may be varied, as desired. Thus the rubber pad gives the cushion a positive shape while the-air pressure within the cushion can bevarled tocorrespond -to the atmospheric pressure.

In the accompanying drawing:

Figure 1 is a left-side elevation of Figure 2;

Figure 2 is an elevation of a seat cushion pro- 35 duced in accordance with the invention:

Figure 3 is a horizontal cross section on line 3-3 of Figure 2; ,i

Figure 4 is a perspective view of a seat cushi in construction; and

n Figure 5 is a detail cross section of the valve 1 means. l

Ziteferringv specificallyV to the drawing, asponge or cellular foam rubber pad I0, which may be made from other.suitable resilient material, is

45 provided as the body of the seat cushion of the invention. VThe pad Il has a slot ",preferably formed therein adjacent the front portion thereof. A fabric cover, or sheet I2, which may be provided with a skin rubber coating, is

5o placed around the entire surface of the pad so reenforced by any suitable means, such as a rubber gum strip I6 after the pad l0 is inserted therein. Next the seat is made air-tight and this comprises spraying a suitable viscous latexrubber composition thereon, as indicated in Figure 4. 5 Care must be taken to cover all of the surface of the seat, and to saturate the seams in the sheet with the latex. 'I'hen the latex is dried 4to form an air-tight impervious rubber cover l2a around the pad I0, which rubber cover l2a is in yaddition lo to any rubber coating formed on the fabric sheet i2 before it is positioned over the pad Ill. Addi-Y tional 4coatings of latex composition maybe applied to the cushion if desired.

'Ihe seat cushion may be finished by applying means such as a Acover of fabric or other upholstery material, I3 about the rubber cover I2a. This aords an air circulating space outside of the impervious surface of the cushion land also prevents accumulation of moisture on the surface of the cushion.

A valve I4 is secured to the fabric sheet l2, preferably prior to coating it with latex, and the valve extends through the upholstery material I3 to provide a passage for air into and from the pad I0. Figure 3 indicates the porous construction of the pad which readily permits the passage of air therethrough. Thus, alrcan be forced into the pad I0, when desired, to create a greater than I atmospheric pressuren therein although normally it sumces to have atmospheric pressure existing within the pad. The valve I4 is so constructed of the cushion at hignal-titudes to prevent overinfiation; Iair can then be admitted to the cushllon again at lower altitudes merely by opening the valve while removing pressure from the cushb ion to permit the spOnge rubberpad to expand and restore the normal amount of air in 'fthe cushion.

The pad should be provided with corner straps v f1 that are secured to the fabric sheet I2- and 45 that are used in associating the seat cushion with a parachute pack (not shown) Straps-from the parachute extend through the tapered slot il to lsecure thecusliion to the -person wearing the parachute pack and the seat cushion of the in- 50 vention thereby provides a comfortable support for a person sitting upon, or resting lagainst a parachute pack. I

While this seatcuslmirn is particularly recommended for use with pa achutes, it may be used l as a regular seat cushion and the air pressure therein can be varied to provide varying degrees of resiliency in the support. Thus, it can be adapted to take varying sized loads and to suit different individuals with the air pressure coordinating with the rubber pad to provide a resilient support.

In accordance with the patent statutes, we have illustrated and described the structure and method of forming an embodiment of the invention. However, it will be understood that various modifications can be made without departing from the scope of the invention as defined in the appended claims.

What is claimed is:

1. A parachute seat cushion comprising a porous rubber pad having `a tapered slot formed therein, a fabric sheet enclosing said rubber pad but leaving said slot exposemmeans sealing the edges of said fabric sheet, a plurality of corner straps carried 4by said fabric sheet to aid in securing the seat to a parachute pack, an impervious latex rubber coating totally enclosing said pad and said fabric sheet, a fabric cover wrapper around said latex rubber coating, and valve means connecting said pad to the atmosphere whereby the air pressure within the seat can be varied.

maintained constant at any desired value regardless of the load applied to the seat cushion.

3. A parachute seat cushion comprising a porous rubber pad having a hallowed-out `center portion and a slot extending therethrough adjacent the front edge or the pad, said slothaving an edge which tapers downwardly towards the rear of said pad to aid in securing it to a parachute pack, means forming an impervious layer over the surface of said pad, and a valve associated with said means for varying the pressure in said pad.

4 A seat cushion comprising a porous rubber pad having a. slot extending therethrough, said slot having an edge which tapers downwardly towards the rear of the pad to aid in securing the cushion to a person, said tapered edge being of substantial area to render the 4portion of the pad thereabove appreclably more resilient than the remainder of said pad', means forming an impervious layer over the entire surface of said pad but leaving said slot exposed,v said means being in intimate contact with the entire surface of said pad, and valve means carried bysaid means whereby the air quantity in said pad can.

be* varied to control the stiifness of said pad but is maintained at any given value regardless of the load applied to said pad.

5. A parachute seat cushion comprising a porous rubber pad having a slot having an edge of substantial area which tapers downwardly towards the rear of the pad formed therethrough to aid in'securing the cushion to a parachute pack, a fabric envelope enclosing said rubber pad and covering all of the surface thereof but exposing,

said slot, said rubber padtotally filling said fabric envelope, a rubber coating associated withsaid fabric envelope to form an air-tight cover around said rubber pad, and valve means carried by said fabric envelope whereby the quantity of air in said pad can be varied to control I the stiffness of said rubber pad butis maintained at any given value regardless of the load applied thereto. l RICHARD M. STONE.

ALAN E. RATHBUN. 

